Rotary boring-drill.



H. H. HUGHES.

ROTARY BORING DRILL.

APPLICATION FILED OCT- 29. I9l8.

l .$22,696. Patented Nov. 25, 1919.

2 SHEETS--SHEET I.

IS naa l 5 H @Moz 13 H. R. HUGHES.

ROTARY BORING DRILL.

APPLICATION man ocT.29, 1918.

HOWARD B. HUGHES, OF HOUSTON, TEXAS.

ROTARY BORING-DRILL.

To all whom t may concern:

Be it known that I, HOWARD a citizen of the United States,vresid1ng at Houston, Harris county, Texas, have invented a certain new and useful Improvement in Rotary Boring-Drills, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to rotary boring drills for .use in drilling wells ory mines in earth or rock. It has particular application to drilling in hard formations but will also operate eiiciently in soft material.

My device is of the type of rotary drills usually included under the term roller bits, wherein the disintegration of the mate- 'rial is brought about by the rolling of toothed cutters upon thebottom of the hole, thus serving to break up and pulverize the material which is then washed away and carried in suspension to the surface by means of a current of iushing water. This ushing water is pumped down to the bit through a hollow drill stem and through channels in the bit and finds an outlet upwardly around the sides of the bit and the drillA stem carrying with it all disintegrated material.

-An object of my invention isto provide a roller bit `of the character described which will operate in both hard and soft formations and which .will be particularly efcient in grinding up and disintegrating the material in such manner that it may be carried from the hole by a stream of flush- Another object is to construct a drill bit which will cut rapidly and which will not easily be "reduced in gage so as to. cause the head of the drill to lodge inthe hole.

Other objects and advantages will bepointed out with more particularity in the specifications which follows and 'thejpoints of novelty will be set forth in greater detail in the claims. .g Referring to the drawings `forming a part of this specification and wherein like numerals are applied to like partsthroughout the several views: Figure -1 is a side elevation'ofmy invention, one of the. side cutters being shcwnin section. Fig. 2 is an elevation taken ati-ight angles/to4 the posi- Specication of Letters Patent.

Application filed October 29, 1918. Serial No. 260,087.

R. HUGHES,

'.ment to the drill stem not shown.

tral bearing Patented Nov. 25, 191.9.

tion shown in Fig. 1, with one of the side sections ofthe bit removed. Fig. 3 is a bottom plan view of my invention.

Figs. 4 to 9y inclusive are diagrammatical views illustrating several diiferent formations of cross cutters and also illustrat- 'ing different ways of inclining the said cutters from the central axis of the bit.

The head of my improved bit is approximately cylindrical in'outline and has a reduced upper threaded shank 2 for attazhhe threaded shank 2 is further reduced in diameter to form a threaded nipple 3 to which a lubricator, not shown, may be attached`l The headv of my bit is split longitudinally along a central dividing line 7 The inner faces of the longitudinal sections are recessed for a distance approximately the length of the lower half of the bit, to receive a central removablel web 4.

The lower end of the bit is provided with two sets of cutters; one set of cutters 8 are mounted in an offset position between an outer .supporting lug 9 and a central support 10 in the central web 4. These cutters are preferably frusto-conical in shape, as shown particularly in Fig. 3 and provided with longitudinal teeth for cuttingv purposes, the innerends being beveled at `30.

On each side of the two central cross cutters 8, I have provided an inclined side cutting disk 5. These cutters are mounted upon pins integral with the side sections of the head. Each of the'cutters 5 is frustoconical in shape and provided with teeth 6 on-the outer cutting periphery thereof. The

pins 11 upon which said disks are mounted are en these cutters are assembled upon theside of the head the threading -of the cenmember 13 upon the shaft 11 is accompllshed by the use of a Spanner, wrenchwhich is adapted to rotate the bearing member 13 by means `'of the countersunk recesses 15 in the outer face of the said bear,- in Referring particularly to Figs. 1 and 2, 1tv will beseenthat the cross cutters 8 are mounted upon the removable web 4 of the head. This web is recessed at 16 on opposite sides above the cross rollers, providing a housing for the side cutters.

Mounted in the central web 4 above the pilot cutters 5 and 8 are two opposite re-aming cutters 17. These cutters are mounted on vertical Iaxes 18 andv are housed within recesses 19 in the sides of the-web. The cutters are approximately barrel-shaped, being cylindrical along the central ortion and tapered toward each end. en thus mounted, it will be noted that the side cutters are reversible and are adapted to bear atall times upon the sides of the-hole with a rolling action. Should the inclined side cutters 5 be reduced in diameter throu h wear, thus tending to reduce the gage of t e hole, the reamers 17 will serve to ream out the sides of the hole about the pilot cutters thus preserving at all times the proper diameter. The three sections of the head, including the '-two side sections and the central web, are retained in proper assembled' position by meansof a locking bolt or pin 2O which passes through an opening 21 in the head at right angles to the at side of the web 4. The head is further retained in assembled position by the threading'of the upper shank 2 intothe drill stem and further bythe threadi-ng ofl the nipple 3J into -p the lubricator. `Flushing water is conducted from the upper end of the drill -bit down'- wardl through channels 22 to each of the side disk cutters and from the housing thereof to the cross rollers. The channels 22 are so arranged that they will discharge the ushing water into the housing above the cutters, at a point slightly to the front of the axis of the cutter as it rolls upon the bottom of the hole.

Lubrication for the bearings of the cutters is conducted downwardly from the lubricator through channels 24 in the head, said channels having branching ducts 25 leading to the vbearings of the two side cutters and threughaiucts 26 to the cross cutters. -Lateral branching ducts 27 also conduct'lubrication to the bearings of the two reaming rollers 17.v y

By referring to Fi'g. 3 it will be seen that the two cross roller cutters 8 are offset from an opposite position in such manner that'the forward advancing face of the cutters, as the bit is rotated ina counter clockwise direction'as viewed in Fig. 3, will be set somewhat inwardly from the edge of kthe web in which it is mounted in such manner that it will not readily scrape the sides of the hole. The purpose of offsetting these cutters, as shown, is to obtain a slipping or 'scraping action due to the fact that the cutters are not diametrically arranged and also ofthe hole. To obtain a true rolling action .the sides of the same would have to be formed so that if extended, they would terminate in the central axis of the bit. This is not the case in this structure. It is desired however, that the two side cutters 5 have a true rolling motion on the bottom of the hole and for this purpose they are arranged exactly opposite each other and also have the cutting periphery formed with such an angle that,if the sides were extended,4 thev-would terminate in the axis of the bit.

In the operation of such a drill the` two cross rollers 8 will serve to cut away the central portion of the hole and the fact that they are inclined will serve to cut a hole with a somewhat conical-shaped bottom, thus assisting in centering the bit in the hole land preventing any tendency of 'rho A1611 to in the side of the head for the purpose of rovidinff an upward passage for. the flushing water carrving away the disintegrated matter.

While I have shown in Figs. 1 to 3 a preferred manner in which the cross cutters 8 are to be placed, there are several alternative modiiications which may be made'without departing from the spirit of my invention land in Figs. 4 to 9, I have shown diagrammatically several of these contemplated modifications. In Figs. 4 and 5, the cross cutters 8 are truste-conical in shape and inclined upwardly in the same manner as those shown in Figs. 1 to 3 andinstead of being staggered, are inclined slightly toward one side of the central axis of the head in the manner shown in Fig. 4 so that their axes are offset relative to the axis of the head. By thus setting the cutters, a conical-shaped bottom will be provided in the hole, and a true rolling action of the cutters 8"l will also be avoided. When inclined in the manner described the rotation of the head will allow a certain amount of slippage in the cutting parts soas to obtain a scraping, as well as a chisel action of the teeth uponthe bottom lof the hole in an obviousvmanner. Figs, 6 and '7 show a cutter 8 shaped like a cylinder, but beveled at the inner end, instead of truste-'conical and oiiset from each other as shown in Fig. 6, but not inclined. In this liiodiicationl no conical-shaped bottom to the hole is obtained, but by oi'setting of the cutters from a diametrical position in the bottom of the head a pallini mpng action l is obtained in a very eiiilcient manner. In

Figs.` 8 .and 9 I have illustrated how cutters such as shown in Figs. 6 and 7 may be in-Y clined laterally from a` central axis of the head but are not staggered or offset as shown.

in the previous modification. This position of the cutters will obtain the same eect as though oii'set in that it will produce the desired cutting and scraping action upon the bottom of the hole.

In assembling my improved drill the two inclined side cutters 5 will be properly secured u on the lower end of the two side sec- Ations o the head. The reaming cutters 17 will'be then mounted within the recesses 19 in the sides of the web and the axis 18 will be inserted longitudinally in each of the said rollers, the pin being of proper length to come flush with the top of the web, when thus inserted. The two cutters 8 will be then placed in position and the removable pins on which they are mounted will be inserted in the sides of the webinto the central supporting member 10 and securedw in position by means of the set screws 29. The three parts will then be set together in registered position and secured in that 'position by means of the locking bolt 20.

Having thus described my invention, the objects and advantages of which will be apparent without further description what I claim as new 'and' desire to protect by Letters Patent is:

1. In arotary boringdrill, a head conprising two side sections and a central web fitting in recesses in the lower half of said side sections, side cutters on said side sections, and cross cutters and reaming rollers mounted in said web.

2. In a rotary boring drill, a head, a central longitudinal recess in the lower part of the head, a removable web in said recess, two 'outersupports' and a central support on said web, two offset inclined cutters mounted in said supports, means to retain said web `in said recess and outer cutters tocut clearance' for said outer supports.

3. In a rotary boring drill, a head comprising two side sections and shorter central sec'- tion fitting removably inrecesses in said side sections, two opposite side cutters mounted on pins integral with said side sections, two offset cross rollers mounted in said cen-l tral section, said central section being recessed on each side tov pro-vide a housing for said Side cutters. i

4. In a rotary boring drill, a head comprising two side sections recessed for the lower half of their length, a central webin said recess, two cross roller cutters on vsaid web, said cutters being so arranged as to have a combined sliding and rolling action on the ibottom of the hole.

5. In a. rotary boring drill, a head comprisingtwo sidesections recessed for the lower half of their length, a central web in said recess, a side cutting disk on each of the side sections and a cross roller.. mounted on said web comprising two oset inclined frusto-conical shaped cutters. l

6. In a rotary boring drill, a head corniprising two side sections recessed on their inner faces for a portion of their length, a vcentral web in said recesses, inclined disk shaped cutters. rotatable on Vpins integral V,with said side sections and a series of cross f disk shaped cutters on said side sections, a

cross roller mounted on said web compris-y ing two cutters each mounted on an outer support and a central support and oHset laterally relative to the central axis of the bit to give a scraping action thereto.

In testimony whereof, I hereunto aiix myv` signature this the 26th day of October, 1918.v

' lHGVVARD It. HUGHES. 

